Gyro apparatus



E. KLAHN.

GYRO APPARATUS.

APPLICATION FILED NOV. 8.1915

latvntud July 15, 1919.

4 SHEETS-SHEET I.

E. KLAHN.

GYRO APPARATUS.

APPLICATION FILED NOV. 8. 1915.

PatentedJuly 15, 1919.

E. KLAHN.

GYHO APPARATUS.

APPLICATION FILED NOV. 2. I9I5.

lzItI-ntcd July 15, 1919.

E. KLAHN.

GYRO APPARATUS.

APPLICATION FILED NOV. 8. 5915. 1,309,637.

Patented July 15, 19.19.

4 SHEETS-SHEET 4- Qnvewboz To all whom it may concern:

sra'ras PATEN BEIGE.

Specification 01' Letters Patent.

Patented July 15, 19119.

Application filed November 8, 1815. Serial No. 60,181.

Be it known that I, EMIL KLAHN, a citizen of the United-States, and resident of New Vernon, in the county of Morris and State of New Jersey, have invented certain new and useful Im rovements in Gyro Agparatus, of which t e following is a speci cation.

The invention relates to gyroscopic apparatus, particularly to such wherein the axis of the rotating mass is designed to remain substantially tangential to the meridian z. e., the axis will maintain a substantially northsouth direction irrespective of the particular latitude at which the apparatus may be located or to which it may be transported.

Instruments of this character are particularly applicable to non-magnetic or so-called gyro-compasses. for use in navigation; and the present application is more especially concerned with this embodiment of the invention, although it is to be understood that said invention is not restricted thereto but is of general application.

The invention has for its object to so construct a device of this character that not only will the spinning mass be automatically and rapidly returned to a north-south position when displaced therefrom, but when in this position will be positively maintained therein, 2'. e. will follow the meridian under the influence of" the earths rotation and which position will, moreover, not be disturbed by a change in the latitude of the place. For this purpose, the instrument is so mounted as to leave its spinning mass substantially three degrees freedom of rotation. Being free from the effects of rotary impulses about its vertical axis, the roscope is, therefore, .not subject to the lnfluence of the vertical component of the earths rotation.

The construction, however, is such as to make the gyroscope subject, under certain conditions, to the influence of the horizontal component of the earths rotation I and to certain auxiliary influences, as will hereinafter he set forth.

In the accompanying drawings, which illustrate the invention- 4 1 Figure 1 is an elevation of the compass, partly in section.

Fig. 2 is a plan thereof.

Fig. 3v is a side elevation of the spinning mass and mounting therefor as well as of the automatic return mechanism; and Fig. 4.-

is an end elevation thereof, both views bemg on an enlarged scale.

ig. 5 is a vertical section through. the spinning mass and a portion of its base and on an enlarged scale.

Fig. 6 is a horizontal section through the. spinning mass and on an enlarged scale.

Fig. and Fig. 8 are vertical sections taken on the lines 7-7, and 8-8, Fig. 5, and looking respectively in the directions of the arrow;

- Similar characters of reference designate corresponding parts throughout the several views.

In carrying out the invention, I prefer to employ a gyroscope of the type disclosed in my prior S. application, Serial No. 854863, filed the 3rd day of August, 1914, and driven in the manner disclosed in a further application, Serial No. 854864, and filed by me the 3rd day of August, 1914:. No

. claim, however, is made in the present application for the specific details shown in the two aforesaid applications; and it is to be understood that I do not restrict myself in the present application to any particular type of gyroscope nor to the manner of drivingithe same.

eferring to the drawings, 10 designates a supporting base or frame to which the apparatus is hung in suitable g' bal supports 11, as is well understood. '%e' apparatus proper consists of a base portion or support 12 whose upper surface is provided with a spherically dished portion 13 which is adapted to partly sustain, when the gyroscope is not in operation, a hollow cylinder 14 having its under surface similarly curved to conform to the dished portion 13 in which its lower end is placed.

Under certain conditions, hereinafter more fully set forth, the said cylinder 14 may rotate freely about its longitudinal (vertical) axis and, furthermore, relative motion between the support 12 and the cylinder 14 will be possible. The said cylinder, moreover, is adapted to be supported, preferably above its center of gravity upon a hollow stem 15 centrally disposed in the interior of the cylinder and fixedly secured to the base portion or support 12. At its upper end, stem 15 is provided with a cone pivot 16 fitting within a guiding recess 17 of the inner surface of the cylinder top. When free from said supports, cylinder 14 may rotate about its longitudinal axis, which axispasses substantially through the pivot. 16; the said axis, furthermore, constitutin the vertical axis of the gyroscopel To e set this freedom from its support, the cylinder 14 is adapted 'tobe sustained by a suitable fluid as, for example, air under proper pressure, said fluid being conducted into the interior of the cylinder from asuitable supply (not shown) through a connection 18 and the said hollow stem 15 and lateral openings 19 at the ofiter end of said stem. About the end of the stem is attached a hollow cap 20 which carries also the pivot 16, and this cap is provided with lateral openings 2* and upper openings 22 discharging into the interior of the cylinder. The cap 20 is vertically slidable upon the stem 15, its lower: most position being fixed by means of an abutment or stop 23 of the stem. To limit the upward movement of said cap, the same is provided with a lug" or ring 24 which is adapted to engage wlth upwardly extending fingers 25- of a nut 26 screwed upon the abutment 23, a spring 27 being interposed between the cap 20' and the abutment 23 to .as'sist the fluid pressure in freeing the cyl- Iinder .14. from support 12. By means of the foregoing, the vertical movement of the cap 20 under the. action of the incoming fluid may be restricted to that'necessary to properly guide, or rather prevent, the cyl- 'inder 14 from anypossibility of displacement of its proper vertical position through the cooperation of the'cone 16' and recess 17. It is understood, however, that there will be no actual contact, but that the cylin- (hr 14 is sustained by the column' of air within and all friction thereby eliminated. 1

When the air support is withdrawn, the adjustment is such that the'entire cylinder and other mechanism hereinafter described will be sustained substantially by the support or base 12 rather than by the cap 20 and stem 15. On restoring the air support, the spring. 27 will serve, also, to cause the cap to follow the upward movement of said cylinder until it abuts the fingers.

The cylinder 14 carries at its top, as by means of suitable standards 30 and other mechanism hereinafter set forth, a hollow rotatable spinning mass 31 which is in the form of a sphere or a portion thereof and its periphery and the sur constructed in separable halves, and with its center coinciding substantially with the center of rotation. The periphery of said.

mass is perfectly smooth and is adapted to run in a corresponding spherical cavity 32 of the upper portion ofsaid cylinder. The

extent of said cavity surface may be va-- ried to suit the different applications of the apparatus, and the said mass is so mounted with respect to the said cavity, as to leavea shallow passage-way 33 between ace of said cavity. The two said surfaces are mounted concen- :tricall {the radius of curvature of flone -.be-

ing s ightly greater than the other-the exact difference for best results being de-. termined by-trial and computation;

The .fluid. to effect the rotation of mass 3Iis. arranged tobe directed into'the passage-way 33 through a suitable nozzle 34, prefegably flat and which communicates with the interior 14 through a duct 35, the said nozzle, when the mass 31'is in the plane of the meridian, being directed substantially at a tangent to-the surface of cavity 32 and symmetrlcally disposed with respect to the f plane of the equator of said rotatin mass.

A stream of fluid isdelivered there y into the passage-way 33 in the nature of a'band and of which there will not be an appreciable lateral flaring as it passes therethrough,

imparting its velocity to the mass 31 and,

also,'c ounteracting the weight of said mass relatively to the cylinder. mass, therefore, floats substantially free in space above the cylinder 14, the latter being similarly supported as aforesaid with respect to the base or support 12.

- To the cylinder 1411s fixedly attachedia' suitable arm or pointer 36 adapted to cooperate with a compass card or ring 37 graduated in'the usual manner., The card 37 is fixedly attached to the gimbalsupport 11 whereby relative rotation'between the card and pointer (gyroscope) may be conveniently measured. A horizontal rod or shaft -40 is supported by the standards 30 and v The spinning about the samefis mounted for rotation the spinning mass 31 which 'runs upon a frame or cradle 41 .mountedto, oscillate about said shaft'and within the interior of said mass.

shaft 40, that s, the cradle will rock in a plane at right angles to the plane of rotation of the spinning mass, as'by means of sulta'ble pivots 44 extending inwardly from opposite 'ends of said frame into the said shaft. The spinning mass may thus rotate. freely about a'horizontal axis represented by the shaft 40, upon the ball bearings 42, and may rock as a Whole with the frame 41 about the pivots 44 perpendicular thereto.

The cylinder portion 14, upon which said spinning mass is mounted, is perfectly free- 'to rotate about a vertical axis when the air is applied, and the gyroscope, therefore, possesses the desired three-degrees of freedom of rotation. By the mounting hereinbefore described, the spinning mass willbe in neutral equilibrium, its center of gravity coinciding with its center of rotation, and a perfect'b'alance thereof is insured, the said mass with its supporting cylinder l4rotating substantially freely in space. The apparatus is, therefore, not susceptible to pendulous efi'jects originating in the gimbal niountings'or to other motions of the su port 12"; and any pendulous motions of t e cylinder 14 itself would, furthermore, be withouteflect upon the spinning mass 31, in view of the herelnbeforedescribed novel suspension. Barring purely accidental disturbances; therefore, the said cylinder is continually maintained in the plumb line.

Being thus freely suspended, the gyroscope-is eiitirely free from the effects of rotary influences about its vertical axis and is, therefore; .not affected by the vertical component of the earths rotation. With respect to the horizontal component of ,the earths rotation, provision is made whereby the same may be employed to automatically affect the gyroscope to cause its axis to fo lo meridian that is tosay, the said component will be effective in producing a precessional force as soon as the axis of rotation of the gyroscope'is thrown out or tends to leave the plane of the meridian. This effect is-obtained without destroying the freedom of rotation .of the gyroscope about the three axes. J 1

To this end, there is mounted upon the shaft 40 and in the plane of the axis of said shaft a se ental gear 50 whose teeth engage the teeth of a pinion 51 mounted upon a freely rotatable shaft 52 carried by the cradle frame 41. To this shaft and upon both sides of the said pinion are .fixedly' attached segmental gears 53 whose teeth engage with: the teeth of pinions 54 mounted to be freely rotatable upon the pivots 44 for the cradle or frame 41, or about an axis perpendicular to the shaft 40. So far as the actual resistance to the rocking of said cradle or frame affects the freedomof the gyroscope, the gearing hereinbefore described is substantially without effect, and the gyroscope will continue to possess the desired three degrees of freedom of rotation. Nevertheless, the lateral thrust developed iii the transmission of the earths rotation through this gearing willbe sufiicient to affect said frame 41, producing thereby .aprecession ofthe gyroscope, as hereinafter set forth. When the axis of rotation of mass 31 is displaced from, or swings out of, its position in the meridianbeing directionally unchanged in absolute space-the mass 31 will assume an apparent (i. e. relatively to the earth) tilt about a horizontal axis to a degree depending upon the extent or theangle of the displacement, while the shaft 40 remains horizontal. This apparent tilting of the mass 31 relatively to w the the shaft 40, which latter follows the earths This lateral thrust reacts upon the frame or cradle 41 to effect an actual (z'. a. relatively to absolute space) tilt of the same about "he pivots 4-4. If this ratio be made laige enough, the side trains may be omitted, and

I do not wish to restrict myself to any particular type or combination of gears to effect the desired lateral precessional force. This tilting of the cradle 41 will be communicated to the mass 31 attached thereto and effect a precession thereof, which precession in due course returns the said mass to the meridian position.

When the mass 31 is considerably displaced from the meridian, the precession produced, as hereinbefore explained, though appreciable, may be insufficient to effect a speedy restoration of the said mass to its meridian position. Additional means to( accelerate the return are, therefore, provided, reference being had more particularly to Figs. 3 and 4 of the drawings. As shown therein, the standards 30 are each provided with a bracket 61 extending outwardly and carrying suitable means for producing precession, for example, weights 62, slidably mounted therein for vertical movement. A frame 63, connected to the cradle or frame 41 and movable therewith, extends about each end of said shaft 40 and about the standards 30. To said frames 63 are attached upwardly directed contact members or plates 64 whose surfaces are normally out of contact with the bpttom of the weights 62, but are adapted to cooperate therewith when the frame 41 is correspondingly tilted. One or the other of the weights 62 will then be engaged by its corresponding plate 64, which will bear the same and will communicate through frames 63 and 41, the pressure exerted thereby, to the mass 31, overbalancing the same, and rapidly effect its precession to the meridian position.

I claim .1. The combination with a gyroscope, mounted in substantially three degrees of freedom of rotation; of gearing, in connection therewith, having a predetermined velocity ratio and so mountedas to develop a on said shaft and rotatable therewith in the plane of said shaft, and two pairs of' 'ear wheels, one upon each side of sad named pair, Connecting the same with said rotatable mass.

4. The combination with a gyroscope, mounted in substantially three degrees of freedom of rotation; of a shaft with respect to which the rotatable mass of said gyroscope may be tilted, a segmental gear fixed to said shaft in the plane of its axis, a pin ion meshing. therewith, a shaft driven by said pinion, two se ental gears, one upon each side of said 'plnion and rotatable with said pinion shaft, and two pinions carried by said rotatable mass and freely rotatable relatively thereto, said two pinions meshing with the respective said two segmental gears.

5. The combination with a gyroscope, comprising a mass free to rotate about two mutually perpendicular axes, and a support therefor freely rotatable about a vertical axis; of a shaft carried by said support and upon which said rotatable mass may be tilted about an axis perpendicular to said shaft; and gearing driven by said shaft and connecting the same to said rotatable mass, said gearing being rotatable in a plane perpendicular to the plane of rotation of said .7

mass.

6. The combination with a gyroscope, comprising a mass free to rotate about two mutually perpendicular axes, and a support therefor/freely rotatable about a, vertical axis; of a shaft carried by said support; a

cradle pivotally attached to said shaft to rock about an axis perpendicular thereto and upon which cradle is rotatably mounted said mass; and gearing driven by said shaft, rotatable ina plane perpendicular to the plane of rotation of said mass and connecting said shaft with said cradle.

7. The combination with a gyroscope, comprising a mass free to rotate about two mutually perpendicular axes, and a support therefor freely rotatable about a vertical axis; of a shaft carried by said support; a

"cradle pivotally attached to said shaft to rock about an axis perpendicular thereto and upon which cradle is rotatably mounted said mass; gear wheels carried by said shaft and driven thereby; and gear wheels carried by said cradle and meshing with said firstnamed gear wheels. 4

8. The combination with a gyroscope, comgyroscope egrees o rstprising a mass free to rotate about two mutually perpendicular a. and a support thereforfreely rotatable about-a vertical axis; a cradle pivotally attached to said haft to rock about an. axis perpendicular thereto and upon which cradle is rotatably mounted said mass; a segmental gear fixed to said shaft in the plane of its axis, aprliion meshing therewith, a shaft drivem'by. "said pinion, two'se ental gears, one upon each side of said pinion and rotatable with said pinion shaft, and two'pinions carried I by said cradle and freely rotatable'relatively thereto, said two pinions meshing with the respective said two segmental gears.

9. The combination with a gyroscope ineluding a hollow, rotatable shell mounted in substantially three degrees of freedom of rotation; of means contained therein, subject to the effect of the-horizontal. component of the earths rotation, to impart to the said gyroscope a precession producing force through the act1on'of said horizontal component on said means.

10. The combination with a gyroscope,

comprising a hollow, rotatable shell free to rotate about two mutually perpendicular horizontal axes, and a support therefor freely rotatable about a vertical axis; of a shaft carried by said support and passing through-said shell; a cradle mounted within said shell, pivotally attached to said shaft to rock about an axis perpendicular thereto and upon which cradle said mass is rotatably mounted; and gearing driven by said shaft, rotatable in a plane perpendicular to the plane of rotation of said shell and connecting the shaft with said cradle.

11. The combination with a. gyroscope comprising a hollow, rotatable shell free to rotate about two mutually perpendicular horizontal axes, and a support therefor freely rotatable about a vertical axis; of a shaft carried by said support and passing through said shell; a cradle mounted within said shell, pivotally attached to'said shaft to rock about an axis perpendicular thereto and upon which cradle said mass is rotatably mounted; a segmental gear fixed to said shaft in the plane-of its axis, a pinion meshing therewith, a shaft driven by said pinion, two segmental gears, one upon each side of said pinion and rotatable with said pinion shaft, and two pinions carried by said cradle and freely rotatable relatively thereto, said two pinions meshing with the respective said two segmental gears.

- 12.,;The combination with a gyroscope bomprising an air supported mass free to 'rotate' about two mutually perpendicular horizontal axes, and an air supporting carrying member therefor free to rotate about avertical axis; of means, subject to the effect of the horizontal component of the earthsrotation, to impart to the said gyroscope a precession reducing force through 'the action of said horizontal axes, and an air supported carrying member therefor free to'rotate about a vertical axis; of gearing, subject to the effect of the horizontal component of the earths rotation, to impart to the gyroscope a precession producing force through the action of said component on said gearing.

14. The lcombination with a gyroscope comprising an air supported mass free to rotate about two mutually perpendicular horizontal axes, and an air supported carrying member therefor free to rotate about a vertical axis; of a shaft supported by said carrying member; a cradle pivotall attached to said shaft to rock about an axls perpendicular thereto and upon which cradle is rotatably mounted said mass; and gearing driven by said shaft androtatable in a plane perpendicular to the plane of rotation of said mass and connecting the shaft with said cradle.

15. The combination with a gyroscope, comprising a mass free to rotate about two mutually perpendicular horizontal axes, means to direct a stream of air thereto to effect the spinning of the same, and an air supported carrying member for said mass and freely rotatable about a vertical axis;

of means, subject to the effect of the horizontal component of the earths rotation, to impart to the saidgyroscope a precession producing force through the action of said horizontal component on said means.

16. The combination with a gyroscope comprising a mass free to rotate about two mutually perpendicular horizontalaxes; a carrying member for said mass and freely rotatable about a vertical axis; and means to direct a stream of air to said carrying member and to said rotatable mass to sustain the former and effect the spinning of the latter; of means, subject to the effect of the horizontal component of the earths rotation, to impart to the said gyroscope a precession producing force through the action of the said horizontal component on said means.

17. The combination with a gyroscope comprising a hollow, rotatable shell, a hollow rotatable air sustained support therefor, and a nozzle to direct air for driving said shell, said nozzle being carried by said support and communicating with the interior thereof; of means, sub] ect to the effect ofthe horizontal component of the earths rotation, to impart to the said gyroscope a precession producing force through the action of said horizontal component on said means.

18. The combination with a gyroscope comprising a rotatable mass consisting of a portion of a sphere, a rotatable support therefor havinga spherical cavity, concentrio with said mass but of greater radius of curvature, to provide a passage-way, and a nozzle carried by said support to direct a stream of air into said passage-way to effect the spinning of said mass; of means, subject to the effect of the horizontal component of the earths rotation, to impart to the said gyroscope a precession roducing force through the action of said orizontal component on said means.

19. The combination with a gyroscope comprisin a rotatable mass consisting of a portion 0 a sphere, a rotatable, hollow support therefor having a spherical cavity, concentric with said mass but of greater radius of curvature to provide a passage-way, a nozzle carried by said support and communieating with its interior to direct a stream of air into said passage-way to effect the spinning of said mass, and means to admit air to the interior of said support; of gearing connecting said support with said rotatable mass, said gearing being rotatable in a plane perpendicular to the plane of rotation of said mass.

20. The combination with la gyroscope comprising a rotatable mass consisting of a portion of a sphere, a rotatable, hollow fluid sustained support therefor terminating in a spherical surface at the bottom and having a suitable recess in its internal upper surface, a frame provided with a spherical cavity to receive the lower end of said suport, a stem carried by said ,frame, extending into said su port and terminating in a suitable pivot a apted to cooperate with the said recess in the internal surface of the support; of gearing connecting said support with said rotatable mass, said gearing being rotatable. in a plane perpendicular to the plane of rotation of said mass.

21. The combination with a gyroscope comprising arotatable mass consisting ofa portion of a sphere, a rotatable, hollow, fluid sustained support therefor terminating in a spherical surface at the bottom and having a suitable recess in its internal upper surface, a frame provided with a spherical cavity to receive the lower end of said support, a stem carried by said frame and extending into said support, a vertically movable cap thereon, provided with suitable openings and with a pivot to cooperate with said recess, resilient means tending to force said cap upwardly, and means to limit the upward movement of said cap; of gearing connecting said support with said rotatable mass, said gearing being rotatable in a plane perpendicular to the plane of rotation of said mass. s

22. The combination with a gyroscope comprisin a'rotatable mass consisting of a portion 0 a sphere, a rotatable, hollow support therefor having a spherical cavity, concentric with said mass but of greater radius of curvature to'provide a passage-way, a nozzle carried by said support and communicating with its interior to direct a stream of air 1nto said passage-Way to effect the spinning of said mass, and means to admit air to the interior of said support; of a shaft carried by said hollow rotatable support; a

cradle pivotally attached to said shaft to rock about an axis perpendicular thereto and upon which cradle is rotatably mounted said mass; and caring drlven through said'shaft and rotwta le in a plane perpendicular to the plane of rotation of said mass and connecting said shaft with said cradle.

The combination with a gyroscope comprising a rotatable mass consisting of a portion of a sphere, a rotatable, hollow support therefor having a spherical cavity, concentric with said mass but of greater radius of curvature to provide a passage-way, a nozzle carried by said support and communicating with its interior to direct a stream of air into said passage-way to effect the spinning of said mass, and means to admit air to the interior of said support; of a shaft carried by said hollow rotatable support; a cradle pivotally attached to said shaft to rock about an axis erpendicular thereto and upon which crade is rotatably mounted said mass; a segmental gear fixed to said shaft in the plane "of its axis, a pinion meshing therewith, a shaft driven by said pinion, two segmental gears, one upon each side of said pinion and rotatable with said pinion,

shaft, and two pinions carried by said cradle and freely rotatable relatively thereto, said two pinions meshing with the respective said two segmental gears.

24%. The combination with a gyroscopecomprising a rotatable mass consisting of a portion of a sphere, a rotatable, hollow, fluid sustained support therefor, terminating in a spherical surface at the bottom and having a suitable recess in its internal upper surface to provide a passage-way, a frame provided with a spherical cavity to receive the lower" end of said support, a stem carried by said frame and extending into said support, a vertically movable cap thereon provided with suitable openings and with'a pivot to coiiperate with said recess, resilient means tending to force said cap upwardly, and

means to limit the upward movement of said cap; a nozzle carried by said support and communicating with its interior to direct a stream of fluid into said passage-way toeffeet the spinning of sald mass, means to admit fluid to said stem; of a shaft carried b .said hollow rotatable support; a cradle pivotally attached to said shaft torock about an. axis perpendicular thereto and upon which cradle is rotatably mounted said mass. a segmental gear fixed to said shaft in the plane of its axis, a pinion meshing therewith, a shaft driven, by said inion,'two

segmental gears, one upon each side of said pinlon and rotatable with said pinion shaft, and two pinions carried by said cradle and freely rotatable relatively thereto, said two pinions meshing with the respective said two I segmental gears.

mounted in substantially three degrees of freedom of rotation; of means, subject to the eflect of the horizontal component of the earths rotation, to impart to the gyro:

a support therefor freely rotatable about a vertical axis; of means, subject to the efiect of the horizontal component of the earths rotation, to impart to the gyroscope a precession producing force through the action of said component" on said means; and supplementary means to engage with said gyroscope to effect precession of the same.

27. The combination with a gyroscope v 75, 25. The combination with a gyroscope comprising a mass free to rotate about two mutually perpendicular-horizontal axes and having its center of gravity coinciding with its center of rotation, and a supporttherefor freely rotatable about a vertical axis and having its center of gravity inits axis of rotation; of means, subject to theeifect of the horizontal component of the earths rotation, to impart to the gyroscope a precession producing force through the action of said component on said means; and supplementary means to engage with said gyroscope to effect precession of the-same.

28. The combination with a gyroscope mounted in substantiall three de rees of freedom of rotation; 0 means, su' ject to (producing. force. through the.

29. The combination with a gyroscopev ;mounted in substantially three de cos of freedomof rotation; of means, su ject to the effect of the horizontal component of the earths-rotation, to impart to the gyroscope a precession" producing force through the action of the said component on said means;

and vertically slidable masses mounted upon opposite sides of the gyroscope adapted toengage therewith to effect precession of the same.

30. The combination with a gyroscope comprising a mass free to rotate about two mutually perpendicular horizontal axes, and a support therefor freely rotatable about a vertical axis; of gearing in connection therewith and so mounted as to develop a lateral thrust, when affected by the horizontal component of the earths rotation, to impart to the roscope a precession producing force; vertlcally slidable masses mounted upon opposite sides of the gyroscope; and means carried by the gyroscope to engage and support said masses.

31. The combination with a gyroscope comprising a mass free to rotate about two mutually perpendicular axes,- and a support therefor freely rotatable about a vertical axis; of a shaftcarried by said support; a cradle pivotally attached to said shaft to rock about an axis perpendicular thereto and upon which cradle is rotatably mounted said mass; of gearing driven by said shaft, rotatable in a plane perpendicular to the plane of rotation of said mass and connecting said shaft with said cradle; suitable brackets carried by the support for the rotating mass, and weights slidable therein; and suitable supports carried by the cradle adapted to engage and support said weights.

32. The combination with a gyroscope mounted in substantially three degrees of freedom of rotation; of means normally] without effect upon the gyroscope, adapted to be engaged by the said gyroscope to aflect therefor its equilibrium and thereby produce a precession thereof when the gyroscope has been disturbed a predetermined amount.

33. The combination with a gyroscope mounted in. substantially three degrees of freedom of rotation; of auxiliary mass, normally without effect upon the gyroscope, to engage with the said gyroscope to produce precession of the same.

34. The combination with a gyroscope mounted in substantially three degrees of freedom of rotation; of vertically slidable masses mounted upon opposite sides of the gyroscope adapted to engage therewith to produce precession of the same.

35. The combination with a gyroscope comprising a mass free to rotate about two mutually erpendicular axes, and a support Freely rotatable about a vertical axis; ofa shaft carried by said support; a cradle pivotally attached to said shaft to rock about an axis perpendicular thereto and upon which cradle is rotatabl mounted said mass; suitable brackets carrled by the support forthe rotating mass, and weights slidable therein; and suitable supports carried by the cradle adapted to engage and sugport said weights. lgned at New York, in the county of New York, and State of New York, this 5th day of November, A. D. 1915.

EMIL KLAHN. 

